Virus-like particles (VLPs) are complex structures formed by self-assembling viral proteins without the presence of the viral genome. The VLP platform is increasingly used to enhance target-specific immunogenicity. VLPs can be produced in several expression systems, including plants. Production of VLPs in plants offers additional advantages, including safety and time efficiency. However, formation of VLPs in plants is part of a physiological process and results in formation of particles of various sizes and shapes, making commercial manufacturing and a smooth regulatory path highly challenging. The size of wild-type influenza virus particles depends on the strain and varies between 70 and 270 nm (Nayak et al., 2009, Virus Res 143(2):147-161). Plant-produced influenza viral particles (VLPs) have different shapes and a broad size range. For example, enveloped pleiomorphic influenza VLPs have been reported to be 100 to 150 nm in size. (Vezina et al., 2011, BioPharm International Supplements 24(5):s27-s30). Thus, there remains a need for more uniform VLPs suitable vaccine development.